NEW YORK 
Rodrigo Sanchez and Gabriela Quintero slipped a little present in with their new album: a DVD tutorial of how to play one of their songs.

Yeah, good luck with that.

Pop that disc in and you'll quickly find out why this acoustic guitar duo known as Rodrigo y Gabriela have a legion of fans transfixed by their unmatchable, frantic fretwork.

Still, it was a nice gesture.

"I know there are a few musicians who don't like to share their tricks but I think that's silly," says Sanchez, 35, by phone from western Mexico as he and Quintero rest up for a U.S. tour. "To share music is something I think everyone should do if they know how to play."

These two definitely know how to play. Their sophomore album, "11:11," recently debuted at No. 1 on the Billboard World Albums chart, hit No. 12 on the Rock Album list, and peaked at No. 34 on the Billboard 200.

Both began playing in a little-known Mexico City speed-metal band. They then teamed up, moved to Ireland and played unplugged Slayer tunes on the streets of Dublin until the 2006 release of their self-titled U.S. debut.

Describing what they do isn't easy: With Sanchez's mesmerizing finger-picking and Quintero acting as the rhythm section – complete with drumming on the guitar body – they meld the power of thrash metal with fiery Spanish melodies. It's hard to believe just two people playing guitars can make music this powerful and absorbing.

"You can make aggressive, fast music from just strings," says Quintero, also 35. "Mentally, we are still a rock band and we still make music that way. It's the energy of a different technique."

The new CD dedicates 11 songs to 11 of their musical influences, ranging from old-schoolers like Jimi Hendrix and Carlos Santana to metalheads like Dimebag Darrell of Pantera to world-fusion pioneers like Al Di Meola, Paco de Lucia, and Strunz and Farah.

There are a few non-acoustic guitar touches – Alex Skolnick of the band Testament adds an electric solo to one song and Sanchez's brother adds piano to another – but the duo insist they aren't wavering from their core sound, whatever that is exactly.

"Honestly, we don't know either," says Sanchez, laughing.

"Music is music. It speaks with one language," says Quintero. "We divide it and label it, but the bottom line is that the expression is the same."